A variety of prostheses have been proposed for the repair or replacement of diseased or damaged ligaments, in particular the anterior cruciate ligament.
U.S. Pat. No. 4,605,414 discloses a process for such a repair wherein the damaged ligament is removed and a strip of patellar tendon is combined with a sleeve of synthetic biocompatible material thereby creating the new anterior cruciate ligament.
U.S. Pat. No. 4,597,766 discloses a ligament replacement which is comprised of a naturally occurring ligament or tendon isolated from an animal source tanned with a bifunctional reagent capable of crosslinking biological tissue. The ligament is fixed in place by attachment of a dicalcified chip of bone which is shaped to receive and retain the bioprosthesis.
U.S. Pat. No. 3,953,896 discloses a prosthetic ligament used to replace a damaged cruciate ligament. In this patent, the prosthetic ligament includes a cylindrical central portion of polyethylene and threaded outer portions provided with bushings to protect the central portion from abrasion caused by skeletal flexing. Fasteners, in the form of nut members, are also provided to fasten the prosthesis within the skeletal apertures.
U.S. Pat. No. 3,545,008 discloses a tendon prosthesis which consists of a Dacron mesh sleeve sutured to the proximal ends of a ruptured tendon. The sleeve includes a mesh netting at its outer ends to encourage fibroblastic infiltration to occur between the severed ends of the tendon for anchoring the prosthesis to the tendon.
U.S. Pat. No. 4,187,558 relates to a prosthetic ligament positioned within a surgically prepared passageway in the bone, and a Dacron or Dacron and silicone strand is disclosed as a replacement for a cruciate ligament with Dacron velour fabric used as collars at the outer ends of the central portion of the prosthesis to promote new tissue growth.
U.S. Pat. No. 3,797,047 discloses an artificial tendon material which consists of a tubular sheath of silicone elastomer with an inner tensile element of knitted fabric.
U.S. Pat. No. 3,805,300 discloses a tendon which is composed of a cord-like combination of silicone and Dacron strip with transverse openings for the natural tendon to be woven therethrough.
In these prior art procedures are well documented the various problems and possible solutions for the repair and/or replacement of the anterior cruciate ligament. A major problem that the prior art has not solved is how to make a replacement anterior cruciate ligament perform in substantially the same manner as the natural anterior cruciate ligament.
The prosthesis of the present invention is placed in the appropriate position to reproduce the femoral and tibial anterior cruciate ligament origins, and then tensioned to approximate the anterior and posterior fibers of the normal anterior cruciate ligament. The result is a substantially smoother and more stable natural range of motion in a knee of a patient.